1. Field of Invention
The invention relates to a screw driver, more particularly to a screw driver which includes a handle and an illuminating unit fixed to a slidable member that is mounted slidably on a shank attached to the handle, which shank has an insulating sleeve member provided thereon adjacent to the handle.
2. Description of the Related Art
According to U.S. Pat. No. 5,124,893, there is disclosed a screw driver which includes a handle (A) and a shank (B) having a front end with a tip (B1) for turning a screw and a rear end (B2) fixed to a front end of the handle (A). The handle (A) confines a receiving space to receive a cell means (C) and is provided with an illuminating unit (E) and a connecting means (F) for connecting electrically the illuminating unit (E) to the cell means (C). The screw driver further includes a slidable member (D) mounted slidably on the shank (B). The illuminating unit (E) is fixedly mounted on the slidable member (D). An on-off button switch (G) is operated to actuate the illuminating unit (E).
A main drawback of the above-mentioned screw driver is that the on-off button switch (G) is disposed on the handle (A). In order to provide the button switch (G) on the handle (A), a special mold is required so as to produce the handle (A), which has a particular receiving recess to accommodate the button switch (G). Making a mold with a particular feature is more expensive than constructing a mold with a simple structure.